Which statements are true?

select each correct answer.

6m^2+18m=6m^2(1+3m)

15m^3−6m=3m(5m^2−6m)

32m^4+12m^3=4m^3(8m+3)

40m^6−4=4(10m^6−1)

Given a: b and b: c, find a: b: c. write the ratio in simplest form. a: b=6: 10 and b: c=21: 33

An investment decreases in value by 30% in the first year and decreases by 40% in the second year. what is the percent decrease in percentage in the investment after two years

Aclassmate thinks that solving a system by graphing gives an exact answer when the lines appear to cross at a grid point, but only an approximate answer when they don't. explain why this isn't true.